I have now purchased a variable power supply that goes up to 10A. I have set it to 12.22VDC.
If my jetson has no m.2 video capture card connected, then I saw the system run for 9 hours before i manually stopped it.
However, with a m.2 video capture card ( have one from two different brands), then it will automatically reboot after 10-20 minutes.
I checked dmesg and I can see PCI errors so I created a forum post here to see if we can prevent the errors. PCIe Bus Error
However, I believe the reboot only occurs when OC overcurrent starts to get triggered due to the temperature. And once the OC current starts, that is when I get PCI errors. And then when I get PCI errors, I get a shutdown.
I have also tried using an M.2 extension board to keep the video capture card outside of my enclosure so that it remains cool but that didnt help.